My standalone-PC with Windows XP on it doesn't have that problem, neither my Linux machine. Both are running FireFox as well, the Windows XP machine also IE 5 / 5.5 / 6 (I do testing) and the Linux machine also Konqueror. All without any problems. Even my iMac, also connected via WLAN like my notebook, works with Safari, IE/Mac and Firefox, all three set up the same way.

I've already uninstalled Firefox on my notebook and tried reinstalling -- no success, same error. There's no proxy set up in any of my browsers, I wouldn't know how to set one up either.

Well, getting me to the profile screen with -p worked out. And I could delete my profile as well as create a new one. But what happened next is kind of creepy.

I got a dialog-box. It was empty, except "Ok" and "Cancel". I clicked ok. It happened again. I clicked ok again. I got a bare-bone Firefox. So far so good.

But: Still the same error. "Beim Versuch...".

Actually, I seem to have installed the german version of Firefox (I have the english one everywhere else). But that's not too big of a problem as I'm from Austria and my native tongue is german anyway. The problem is that I cannot access any URL at all with that particular Firefox. Even after creating a new profile.